Dragons are creatures with nearly unlimited life spans. They can survive for long periods of time, and no one has found a dragon that has died of old age. Adolescence is usually marked by the growth of a hatchling's wings, although not all breeds of dragons grow wings and some breeds have other traits that indicate the beginning of maturation. Once they hit adolescence, hatchlings change quickly, maturing to their full forms in only 2 years.

Dragons don't communicate with each other verbally, but they will growl to scare off predators and frighten prey. Young dragons will emit an extremely high-pitched squeal when they are frightened. To communicate, they use telepathy with each other and to speak to other creatures.

Two headed dragons are a special breed of dragons. They have two necks, two brains, two mouths, but one stomach and one main body. The two heads usually work together, but there are times when they will fight each other, attacking back and forth. They use their sharp teeth and wings to hunt large animals, and rarely eat plants. It is unknown what would happen if a two headed dragon were to mate with a one headed dragon, since it has never occurred. They only mate within their breed.

The brothers Thor and Mjolnir are inseparable... literally as well as emotionally. One never makes a decision without the advice of the other, and together they form an unstoppable fighting team. Mjolnir tends to be the more impulsive of the pair, often acting before thinking, and while Thor never passes up an opportunity for a good fight, he tempers Mjolnir's raw emotion into more constructive (and often more damaging) strategies. Both brothers, while not the most clever of dragons, are enormously kind and protective to those weaker than themselves, and cannot stand to see injustice go unpunished. They have recently found love with the legendary fighting sisters Gjalp and Greip after besting them in a spectacular battle--but only just.